基于相位裕度的永磁同步电机位置伺服系统研究

Study of Permanent Magnet Synchronous Motor Position Servo System Based on Phase Margin

提出了永磁同步电机(PMSM)位置伺服系统的相位裕度设计方法,通过在开环截止频率处相位对角频率的导数为零方法,得出了中频区宽度与相位裕度的关系,给出位置控制器参数设计的新方法,在一定中频区宽度下系统具有最大相位裕度,提高系统对开环增益变化的鲁棒性。此外,为了提高伺服系统跟踪精度,按伺服模型构建位置信号的微分观测器,实现了平滑的数字前馈补偿,并针对大误差时的饱和非线性特性,采用"根号"控制策略,提高大角度协调的动态性能。仿真和实验验证了该位置控制算法的有效性。

A phase margin based design method for permanent magnet synchronous motor（PMSM）position servosystem was presented.Relationship of mid-frequency interval width versus phase margin was obtained by setting thederivative of phase to frequency to zero at the gain crossover frequency.A new design method of position controllerparameters was given.A maximum phase margin can be achieved at the same mid-frequency interval width.Therobustness to open loop gain can be improved greatly.In order to improve the system tracking precision,a differentialobserver was established in accordance with the servo model.Smooth numerical feedforward compensation wasachieved.“Square root”control was used against saturation and nonlinear when in large position error.The dynamicperformance of large angle response can be enhanced.Simulation and experiment study are carried out and the resultsverify the effectiveness of the proposed approach.